Let's see if you all might be able to help me here.

I just recently put in my standalone ECU and 550cc injectors, and got it running a few days ago. I got it fairly well tuned, and it's been doing okay, and still is, but a little problem has arisen. I've tried changing some different things on the ECU to correct it, but nothing so far.

Whenever I accelerate then let off the gass, and let it drop into high vacuum, as the RPMs drop it will spout off a good amount of loud pops from the exhaust. Does this have something to do with running way too rich?

Any ideas?

 

im sure thats possible. what type of exhaust/header system are you running?

 

I've more or less got this here.

edit: oh, and I probably should mention I'm using their high-flow cat as well, followed by their 2.25 inch exhaust.

 

Do you have a wideband oxygen sensor.

 

Negative. Still on stock narrowband .

I may take it to a shop and get it dyno tuned with wideband fairly soon, though.

 

too little timing under vacuum conditions.

 

^^^I'll check into that.

I also noticed when I put my hand up to my tailpipe at idle, my hand got a little bit of black shit on it.

 

too much fuel